Disturbance Effects Seen in the Midlatitude Ionosphere with SuperDARN

Abstract:

With the construction of the first midlatitude SuperDARN radar at NASA Wallops Flight Facility in 2005 it quickly became apparent that much activity can be observed in the midlatitude ionosphere even outside of large storm intervals. Over the last five years a chain of SuperDARN radars has been deployed at midlatitudes under the NSF Mid-Sized Infrastructure program that extends across the western hemisphere as far as east Asia. The new radars are providing unprecedented large-scale views of disturbance effects such as the storm-time expansion of auroral flows, subauroral polarization streams (SAPS), and travelling ionospheric disturbances (TIDs). When combined with large-scale mapping of GPS/TEC it is possible to observe directly the generation of plasma structures such as storm-enhanced density features (SEDs), tongues of ionization (TOIs), and polar cap patches, and to understand their dependence on the dynamic convection pattern reaching to the mid-latitude region. One unexpected result is the observation of backscatter from irregularities distributed throughout the quiet-time nightside subauroral ionosphere. This phenomenon gives us views of electric fields that are conjugate to the inner magnetosphere and also reveals the occurrence of large transients in the quiet-time subauroral electric fields. In this talk we summarize over the effects identified to date and discuss the insights gained in understanding the disturbed midlatitude ionosphere.